Understand the Hydraulic Cylinder Seal Failure Better

Its quite surprising that a thing as negligible as Hydraulic cylinder seal can affect the productivity and production cost way beyond one's assessment. Hydraulic seals are relatively inexpensive as compared to the other hydraulic components , but in case the usually underestimated seal fails, it can easily hamper the entire working process. Following are few possible reasons which can lead to seal failure:

Incorrect installation is one of the most common causes of hydraulic seal failure. The seal installation needs to be done with utmost care and precision. The major areas which should be addressed while seal installation are:
-Cleanliness
-Protection of seal from nicks and cuts
-Proper lubrication
Besides, over tightening of seal gland with an adjustable gland, folding over of a seal lip or installing the seal upside down accounts for the common carelessness showed while seal installation.
Another major reason for hydraulic seal failure is the contamination of hydraulic system. The contamination most often is due to foreign elements like dust, dirt, mud, grit etc. or internal elements like break-down products of fluids, circulating metal chips, hoses or other degradable system components. External contamination can easily be avoided by installing the rod wiper/scrapers properly, since most of the foreign elements enter the system during rod retraction.

At times chemical breakdown of seal material can also lead to seal failure. Chemical breakdown of seal material is often due to the incorrect material selection or change of hydraulic system fluid. Moreover, chemical attack by fluid additives because of misapplication or use of non-compatible materials can also be a reason for chemical breakdown. Hydrolysis and oxidation reduction of seal elements being other possible reasons for chemical breakdown. Chemical breakdown ultimately affects the seal by either softening of seal durometer or loss of seal lip interface. Excessive swelling or shrinkage and discoloration of hydraulic seals too speak about the chemical attack of certain nature.

Heat degradation is yet another issue resulting into seal failure. If the hydraulic seal appears to be hard or brittle and depicts the breakage of seal lip or body parts then it is indeed a case of heat degradation. It is most often caused due to high dynamic friction, proximity to outside heat source, usage of incorrect seal material, no heel clearance or excessive lip loading. Simple solutions to avoid such situations include change in the choice of seal material, reduction in seal lip interference and enhancement of upper limits of temperature.